Elevatable self-operated invalid chair



Jam. 28,. 1958 J. R. MANEGOLD 2,821,242

ELEVATABLE SELF-OPERATED INVALID CHAIR Filed March 7, 1955 1- all;

I m x u i" mum-mum 15:1

. John 2 R.

United States Patent C) ELEVATABLE SELF-()PERATED INVALID CHAIR John R. Manegold, Milwaukee, Wis.

Application March 7, 1955, Serial No. 492,417

3 Claims. (Cl. 155--91) This invention relates to a manually operable vertically adjustable invalid chair and more particularly to a compact elevatable invalid chair which is especially useful for raising and lowering an invalid in a bathtub by his own power and with very little effort other than the shifting of weight from one hip and thigh to the other hip and thigh.

Heretofore vertically adjustable invalid chairs have been so constructed that they have required either the services of a third person to raise and lower them manually or have had incorporated therein bulky mechanisms to provide the necessary mechanical advantage whereby the invalid occupant could raise and lower the chair himself. The elevating mechanisms incorporating the mechanical advantage have usually been of the hand operated type.

The energy required to be fed by hand into the mechanisms of such chairs to elevate the occupant thereon is equal to the sum of the weight of the occupant and the weight of the vertically moving parts of the chair multiplied by the mean vertical distance through which the load moves plus any friction losses. A manually operated chair which has a large mechanical advantage requires a lot of hand motion to raise it. A chair without a large mechanical advantage requires a strong hand and wrist to operate it. Where a third person is available this is not a drawback but it is when the work has to be done by the invalid himself, particularly when the invalid is one of that large class of arthritic sufierers who find it difiicult to use their hands, fingers and wrists in a normal manner.

Such persons need a chair which requires only a small amount of energy to be fed for a short time into the chair mechanism by hand to elevate and lower it and which has simplified manual controls to simplify the hand motion itself.

This invention contemplates a compact elevatable invalid chair having load-supporting extensible parts capable of being operated in an unloaded condition by the seated occupant of the chair whereby the energy input into the hand controlled adjusting mechanism of the chair does not exceed the friction loss of moving parts.

The invention further contemplates a chair so compact and light that it may be placed in a conventional home bathtub by an invalid and used by him for lowering himself when seated thereon into the water and raising himself out of the water after his bath.

It is therefore an object of the present invention to provide an improved elevatable invalid chair which requires for elevating the chair with an invalid seated thereon an energy input into its controls of an amount not greater than the friction loss of moving parts of the chair.

Another object of this invention is to provide an improved invalid chair which does not require the services of a third person to operate it. Another object of this invention is to provide an improved elevatable invalid chair which is simpler to construct and easier to elevate than invalid chairs heretofore.

2,821,242 Patented Jan. 28, 1958' Another object of this invention is to provide an improved elevatable invalid chair which can be operated under water.

Another object of this invention is to provide an improved elevatable invalid chair which is laterally stable.

Another object of this invention is to provide an improved elevatable invalid chair which has manual controls easily accessible to the occupant of the chair.

Another object of this invention is to provide an improved vertically adjustable invalid chair which has manual controls simpler to operate than heretofore.

Objects and advantages other than those above set forth will be apparent from the following description when read with the accompanying drawing, in which:

Fig. 1 is a front elevation of an invalid chair embodying the invention, the occupant seated thereon being shown in fragment in dotted line;

Fig. 2 is a side elevation of the invalid chair of Fig. 1;

Fig. 3 is a detail view of the connection between the chair seat and the pivot means of the chair shown in Fig. 1.

The elevatable invalid chair shown in Fig. 1 comprises a pair of horizontally extending spaced stabilizing front and rear members 1! 10' spaced from the ground. The front and rear members 19, it) are rigidly interconnected between their ends by rearwardly extending spaced load supporting or side members 11, 11 suspended from said members Ill, 13 and spaced from the ground a lesser distance than said members 10, 10'. Members 10, 10' and 11, 11' form respectively stabilizing portions and load supporting portions of a rigid base frame 12. Ground engaging means such as resilient suction cups 13 are fastened to the members 10, it) near the ends thereof in spaced relation to members 11, 11. Mounted on and extending upward from the members 11, 11 are extensible means shown as lazy tong means 15, 15. Each lazy tong means 15, 15 comprises dual lazy tongs 16, 16 fastened together in laterally spaced relation to extend and contract together. Although dual lazy tongs 16, 16 are shown making up a lazy tong means 15, 15', a single lazy tongs of equal structural strength could be substituted therefor. The extensible ends of the lazy tong means 15, 15' are connected respectively by pivot means 17, 17' to depending frames 18, 1S fastened to the underside of seat 19 in the following manner. The extensible ends of lazy tong means 15 are operably pinned to collars 6, 7, as shown in Fig. 2. Collar 6 is immovably fastened relative to pivot means 17, which may be a rod, whereas collar 7 is slidably fastened to pivot means 17. In similar fashion lazy tong means 15' is operably pinned to collars, not shown, which are respectively rigidly and slidably fastened to pivot means 17'. The pivot means 17, 17' extend respectively through bearing openings 20 in the frames 18, 18' from front to rear of the chair and are pivotally interconnected by a front stabilizing bar 25 and a rear stabilizing bar 26.

The lateral distance between the pivot means 17, 17' is from 5 /2 to 8 inches but ordinarily is 6% inches since that distance represents the mean distance between the ischia of various occupants pelves when the occupants buttocks and thighs are pressed against the seat 19. The lateral distance between the pivot means should not be substantially greater than 8 inches because the occupants buttocks and thighs when the invalid is seated on the seat 19 must be outboard of the pivot means 17, 17, never inboard of the pivot means 17, 17' when elevating the chair. The significance of this critical spacing of the pivot means will be explained hereinafter in connection with the operation of the chair.

Extensible stabilizing means 29, 34) are respectively connected to the front and rear members it), it) of the base frame 12 and tothe front and rear stabilizer bars 25, 26. Means for extending and contracting each lazy. tong means 15, 15 comprises a horizontally extending screw 33 having opposed threaded sections 34, 34 in respective threaded engagementwith a pair of nuts 35, 35 pivotally connected to the extensible parts 36 of the lazy tong means 15, 15 intermediate the seat 19 and the base .frame 12. The screws 33, one of which is shown in' Fig. 2, have multiple threads to increase the speed of axial travel of the nuts 35, 35 in order to save time changing the height of the chair and to reduce the friction of the threads 34, 34 in the nuts 35, 35' to the safe minimum. The threads 34, 34' have a lead of /6 inch for a screw of /2 inch outside diameter. A lead in excess of inch, for a /2 inch diameter screw will increase the sum of the helix angles of the left and right opposed threads 34, 34' to the point where friction between the screws 33 and the nuts 35, 35' will be overcome by axial pressure on the nuts 35, 35. Screws 33 will then turn because of the weight of the occupant on the seat 19 and the occupant will lose control of the movement of the chair. Therefore, the lead should not be greater than /6 inch for a /2 inch diameter screw and of similar proportion for other diameter screws.

Each of the screws 33 is operated by a \.'-belt sheave 40 attached to the front end of the screw, the V-belt sheave 40 being in turn actuated by an endless V-belt 41 extending upward from a sheave engaging position to a position in front of and substantially level with the seat 19. Means for holding the V-belts 41, 41' in a vertical standing position are attached to the screw means, as shown in Fig. 2, and comprise rigid wire supports 42, 42' having a loop at one end thereof which engages a collar on the sheave 40, 40 and a loop at the other end through which the V-belt 41, 41' passes. Means for holding the V-belts 41, 41 in contact with the bottom of sheaves 40, 40' are provided by the formed wire parts 43, 43 which surround the grooves and lower portions of the sheaves and are attached to the rigid supports 42, 42, as by welding or brazing the upper ends of wire parts 43, 43' respectively to the rigid supports 42, 42'. The supports 42, 42' are respectively held in the position shown in Fig. 1 by frictional engagement of their lower loops with the collars of the sheaves 40, 40. Supports 42, 42 are respectively rotatable relative to the sheaves 40, 40' and vice versa. Thus when the sheaves 40, 40' are rotated by manipulation of the belts 41, 41' from the chair seat, the supports 42, 42' will assume an angular position relative to the sheaves, which angular position corresponds with the direction in which one side of the belt is being pulled through the upper loops of the supports 42, 42'. An occupant in the chair seat will normally pull one side of the belts upwards. The supports will therefore point upward since their upper loops confine the belt. When the belts 41, 41 are not being manipulated the supports 42, 42' maintain the belts in the same position as they were in when being operated. In Fig. 1, supports 42, 42' are shown supporting the upper portion of the belts 41, 41' in a vertically extending position, in which position the bglts are readily accessible to the occupant of the invalid c air.

The chair-is operated as follows: the occupant is seated centrally on the seat 19 as shown in dotted line in Fig. 1. Each of the occupants buttocks is disposed directly over the complementary one of the extensible means 15, 15' when the occupant is centrally seated. To lower the chair from the position shown in Fig. l the occupant leans slightly to one side so as to carry his entire weight on one buttock and thigh and thereby place his entire weight over one of the load-supporting pivot means 17 and lazy tong means 15. The occupant then grasps the V-belt 41' of the other lazy tong means 15 which then is not carrying any portion of the weight of the occupants body and by means of the belt 41' rotates the respective screw 33 to lower the lazy tong means 15 and cause the seat 19 to tilt sideways about the pivot means 17'. Having lowered the lazy tong means 15 to a position in which the seat 19 is tilted, but not to an uncomfortable degree so as to cause the occupant to slip sideways, the occupant leans laterally the other way and without shifting the position of his buttocks and thighs relative to the seat transfers his weight to the other pivot means 17' and lazy tong means 15' and then proceeds to contract the lazy tong means 15 in a similar manner by rotating the V-belt 41 of that lazytong means 15. This operation is repeated, alternately operating that lazy tong means 15, 15 which does not carry any portion of the occupants weight. In this manner the seat 19 is brought as close to the base frame 12 as the folded tong means 15, 15 will permit.

To elevate the seat 19 the occupant leans his weight on one hip and thigh more to the side than he did in lowering himself, so as to carry his weight outboard of one pivot means 17, thereby tending to exert an upward pull on the unloaded side of the seat 19 which in turn exerts an upward pull on the lazy tong means 15, because of lever action about the pivot means 17, as a fulcrum which is inboard of the hip and thigh which carry the occupants weight. The unloaded side of the seat and the lazy tong means 15', can then be raised by merely overcoming the friction between the threads 34, 34 and the nuts 35, 35' by extending the lazy tong means 15' by pulling on V-belt 41 until the seat portion above the lazy tong means 15' reaches a position in which both buttocks and thighs of the occupant are firmly pressed against the seat which is now in a sideways tilted position. The occupant then shifts his weight to his other buttock and thigh which are outboard of the pivot means 17' and proceeds to extend the lazy tong means 15 with the assistance of the V-belt 41 and screw 33 connected thereto. This process is repeated, the occupant alternately seesawing his body and the chair seat 19 by alternately extending each lazy tong means 15, 15' until the desired seat elevation is reached. It will be noted that the distance between the pivot means coincides with the distance between the load pressure points of the average occupants buttocks to allow the occupant to lean sideways in contact with the seat and yet place his entire weight over or outboard of one or the other of the pivot means 17, 17. By the method hereinbefore described the occupant is able to alternately free the lazy tong means 15, 15 fiom carrying any body load, thereby reducing the amount of energy required to be alternately fed into the screw means 33 of the lazy tong means 15, 15. No more energy is required to be fed in than is necessary to overcome friction of the moving parts of the chair, since by tilting the seat. about one pivot means the occupant exerts an upward pull on the other unloaded tong means through the complementary pivot means when elevating the chair. The occupant is thus relieved of exerting any appreciable effort through his hands to operate the chair. He is able to. accomplish the lifting of his body by a seesaw motion cooperating with the alternate extension of the tong means 15, 15', which extension requires little manual effort because of the lightness of the chair parts.

To lower the chair the occupant proceeds in a reverse manner with his weight alternately placed over one or the other of the tong means. He then alternately contracts the unloaded tong means until the chair reaches the desired loaded position.

Although one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without distinguishing from the essence of the invention or from the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. An invalid chair capable of having its extensible parts elevated and lowered in an unloaded condition by the occupant seated on said chair and providing the load thereon, said chair comprising a base frame, a plurality of load-supporting lazy tong means extending upward from said base frame in parallel relation to each other and capable of individually supporting the entire load on said chair, each of said tong means having a base end and an extensible end, said base ends of said tong means being operably mounted in spaced relation to each other on said base frame, screw means for each of said tong means disposed in a median relation between said seat and said base frame and having opposed threaded connections with spaced complementary parts of said tong means, said screw means being respectively rotatable relative to said tong means to extend and contract each of said tong means, said screw means extending forward of said chair and having endless drive means operably connected thereto and accessible to the occupant of said chair for remotely turning said screw means, a seat selectively tiltable about horizontally extending spaced axes in response to extension and contraction of said tong means, pivot means for each of said tong means, said pivot means connecting said seat to said extensible ends of said tong means and extending respectively coaxially with said axes, said pivot means being spaced apart from each other a distance of from 5 /2 to 8 inches to place each of said extensible ends of said lazy tong means in respective direct opposing relation to the central point of seating contact of each of the buttocks and thighs of the occupant of said chair whereby the occupant can transfer his entire weight through one of his buttocks to one of said lazy tongs while remaining in nonsliding contact with said seat to unload the other of said lazy tongs whereby said other of said lazy tong means is extensible and contractible in an unloaded condition.

2. An invalid chair capable of having its extensible parts elevated and lowered in an unloaded condition by the occupant seated on said chair and providing the load thereon, said chair comprising a base frame, dual lazy tong means extending upward from said base frame intermediate the ends thereof in parallel relation to each other and capable of individually supporting the entire load on said chair, each of said tong means having a base end and an extensible end, said base ends of said tong means being operably mounted in spaced relation to each other on said base frame, each of said tong means comprising a pair of parallelly extending lazy tongs, screw means for each of said tong means having opposed threaded connections with spaced complementary parts of said tong means, said screw means being respectively rotatable relative to said tong means to extend and contract each of said tong means, a seat selectively tiltable about horizontally extending spaced axes in response to extension and contraction of said tong means, pivot means for each of said tong means, said pivot means connecting said seat to said extensible ends of said tong means and extending respectively coaxially with said axes and intermediate the lazy tongs of each pair, said pivot means being spaced apart from each other a distance of from 5 /2 to 8 inches to place each of said extensible ends of said lazy tong means in respective direct opposing relation to the central point of seating contact of each of the buttocks of the occupant of said chair whereby the occupant can transfer his entire weight through one of his buttocks to one of said lazy tong means While remaining in nonsliding contact with said seat to unload the other or" said lazy tong means whereby said other of said lazy tong means is extensible and contractible in an unloaded condition.

3. An invalid chair capable of having its extensible parts elevated and lowered in an unloaded condition by the occupant seated on said chair and providing the load thereon, said chair comprising a base frame having spaced ground engaging ends, dual load-supporting lazy tong means extending upward from said base frame intermediate said ground engaging ends in parallel relation to each other and capable of individually supporting the entire load on said chair, each of said tong means extending from the front of said chair toward the rear thereof and having a base end and an extensible end, said base end of said tong means being operably mounted in spaced relation to each other on said base frame, screw means for each of said tong means having opposed multiple thread connections with spaced complementary parts of said tong means, said screw means being respectively rotatable relative to said tong means to extend and contract each of said tong means, said screw means extending forward of said chair and comprising endless drive means operably connected thereto, and means for supporting said drive means within reach of the occupant of said chair whereby the occupant by selectively moving said drive means can remotely operate said screw means, a seat selectively tiltable about horizontally extending spaced axes in response to extension and contraction of said tong means, pivot means for each of said tong means, said pivot means connecting said seat to said extensible ends of said tong means and extending respectively coaxially with said axes, said pivot means being spaced apart from each other a distance of from 5 /2 to 8 inches to place each of said extensible ends of said lazy tong means in respective direct opposing relation to the central point of seating contact of each of the buttocks of the occupant of said chair whereby the occupant can transfer his entire weight through one of his buttocks to one of said lazy tong means while remaining in nonsliding contact with said seat to unload the other of said lazy tong means whereby said other of said lazy tongs is extensible and contractible in an unloaded condition.

References Cited in the file of this patent UNITED STATES PATENTS 278,818 Poolman June 5, 1883 1,088,419 Heyer Feb. 24, 1914 1,807,960 Brownell June 2, 1931 FOREIGN PATENTS 21,147 Great Britain Nov. 19, 1892 

